Calling device



June'30, 1925. 1,543,662

W. T. BOOTH CALLING DEVICE File d llay 2, 1921 Patented June 30, a 1925.

UNITED STATES 1,543,662 PATENT OFFICE.

WILLIAM '1. BOOTH, OF BROOKLYN, NEW YORK, ABSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, 01 NEW YORK, N. Y., A CORPORATION OF NEW YORK.

oamno nnvrcn.

Application filed lay 2,

To all whom it may concern:

Be it known that I, VILLIAM T. Boo rm'a citizen of the United States, residing at Brookl n, in'the county of Kings, State of New ork, have invented certain new and useful Improvements in Calling Dev1ces, of which the following is a full, clear, concise, and exact description.

This invention relates to calling devices of the type commonly employed in auto matic telephone systems for operating the switching mechanism to build up the desired connections.

The object of this invention is an 1 mproved form of calling device, 1n which means is provided for shunting out 1mpulses when the finger wheel is rotated in a clockwise direction, and in which the relative duration of the make and break of the impulse contacts remains constant.

This object is accom lished by providing in combination with t e spring controlled shaft of a calling device of any well-known type, a pair of impulse sending springs and a pair of shunting springs, and means cooperating with the shunting springs to move them into contact to shunt the impulse send- 3 ing s rings during the clockwise rotation of the s aft and to break the shunt during the counterclockwise rotation, together with means cooperating with the impulse sending springs to send out impulses during the counterclockwise rotation of the shaft.

The calling device will be more clearly understood by reference to the followin detailed specification and accompanying rawin s.

%igure 1 is a plan view of a device embodying this invention with parts broken away to show the different members.

Figure 2 is a cross section of the device out along line 2-2 of Figure 1.

F i re 3 shows the positions of the pivoted ever and the shunting springs when the finger wheel is rotated in a clockwise direction.

Fi ure 4 shows the position of the pivoted ever and the shunting springs when the finger wheel is rotated in a counter-clockwise direction. a

Figure 5 is a perspective view of the commutator type interrupter wheel and impulse sending springs.

Referring to the figures mentioned above the base section 1 of the casing has a cylin- 1921. Serial No. 486,086.

drical projection 2 which has an opening therethrough and which forms a bearing for the. shaft 3. Located on the projection 2 is a helical s ring 4, one end of which is attached to t e section 1 of the casing and the other end to a collar 5, which is integral with the shaft 3. Fixed to the shaft 3 is an annular supporting member 6, to which a toothed wheel 7, a commutator type interrupter wheel 8 and a gear wheel 9 are secured by means of bolts 10. The gear wheel 9 meshes with the gear wheel 11 which through a train of gears engages with governor shaft 12. Supported on the base section 1 is a top section 13 of the casing. Lo-

cated on the top section 13 is the number plate 14. Held in fixed engagement with annular member 6 by means of nut 15 which engages with shaft 3 is the finger wheel 16.

The commutator type interrupter wheel 8 consists of two ring shaped members 38 and 39 composed of insulation material. Imbedded in ring shaped member 39 is a toothed wheel 18 which is made of conducting material and the teeth of which project to the surface as shown at 19. Surrounding member 38 is a band of conducting material 40 which is electrically connected to the wheel 18 as shown at 17. The members 38 and 39 are held together by the bolts 10. The relative length of make and break can be regulated by the design of wheel 18.

A supporting member 20 is carried by the casing, and attached thereto by screws 25 are two impulse sending springs 21 and 22 and two shunting springs 23 and 24. Springs 21 and 24 are insulated from 22 and 23 which make electrical contact with one another and all the springs are insulated from the supporting member 20. Springs 21 and 24 are connected to one terminal of the line and spring 22 to the other terminal. Pivoted to the casing is a lever 26 which is held in engagement with the toothed wheel 7 by means of a spring 27 attached to the casing. A roller 28 which is made of insulation material is mounted on lever 26 and serves to prevent the making of electrical contact between lever 26 and spring 24.

A plate 29 havin a projection 30 on its perip ery is carrie by the annular suportmg member 6 and is fastened thereto by means of bolts 10. Roller 33 which is made of insulation material is mounted on plate 29. A stop block 31 is attached to the casing and so located as to engage projection 30 when the shaft is in its normal position.

The springs 34, 35 and 36 are carried by a bracket 37 which is fastened to the casing. These springs are insulated from one another and from the bracket 37. A finger stop 32 is fixed to the casing member 13.

The operation of the device is as follows:

Normally, projection 30 of plate 29 is in engagement with block 31. The pivoted lever 26 is in the position shown in Figure 4 and holds the spring 24 out of contact with spring 23. Spring 27 retains lever 26 in engagement with wheel 7.

lVhen it is desired to establish certain connections, the finger wheel 16 is rotated in a clockwise direction. The finger wheel 16 is fixed to the shaft 3 and as it rotates wheel 7 which is also fixed to the shaft 3 rotates and moves lever 26 to the position shown in Figure 3' and allows spring 21 to make contactwith spring 23. The making of contact between these springs shunts the impulse sending springs 21 and 22. Therefore, the impulse sending springs 21 and 22 which ride on the commutator type interrupter wheel 8 are cut out of the circuit and as the interrupter wheel 8 rotates in a clockwise direction, no impulses are sent over the line.

\Vhen the finger wheel is released the spring 4 rotates the shaft in a counterclockwise direction. The wheel 7 moves lever 26 to the position shown in Figure at and the circuit through the shunting springs 23 and 21 is broken and the impulse sending springs 21 and 22 are connected into the circuit. Therefore, as the interrupter wheel 8 rotates in a counterclockwise direction there is a make and break operation and impulses are sent over the line through impulse springs 21 and 22.

The rotation of finger wheel 16 causes the plate 29 to rotate and as roller 33 moves out of engagement with spring 35, contact is made between spring 35 and spring 34.

lVhen the shaft returns to its normal position the wheel 33 engages spring 35.and forces it out of contact with spring 3 1. These springs are not an essential part of the invention and are only set forth to show an arrangement that might be used to eliminate noise during the operation of the device.

hat is claimed is:

1. In a calling dial, the combination with a finger wheel, a stationary disc having characters thereon, a variably operable shaft for said wheel, an impulse wheel fixed to said shaft, springs cooperating with said impulse wheel, a toothed wheel carried by said shaft, said toothed wheel having a number of teeth corresponding to the number of characters on said finger wheel, and means actuated by the movement of said toothed wheel to render said impulse wheel ineffective with respect to said impulse springs during the setting movement of said finger wheel.

2. In a calling dial, a finger wheel, a sta tionary disc having characters thereon, a variably operable shaft on which said wheel is fixed, a toothed wheel also fixed to said shaft, the teeth corresponding in number to said characters, an impulse wheel fixed to said shaft, springs cooperating therewith, short-circuiting springs, and a member actuated by said toothed wheel at the beginning of the rotation of the wheel in either direction for actuating said latter springs.

3. A calling device comprising a rotatable shaft, a commutator type interrupter wheel, a pair of impulse springs in wiping engagement with said interrupter wheel, a toothed wheel carried by said shaft, 9. pair of springs, and a lever intermediate said latter springs and said toothed wheel cooperating with both to short circuit said impulse springs during the rotation of said shaft in one direction.

In witness whereof, I hereunto subscribe my name this 29th day of April A. D., 1921.

WILLIAM T. BOOTH. 

